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《Brain stimulation》2020,13(5):1381-1383
Across a series of studies, our laboratory has shown that the efficiency of action stopping is associated with the strength of GABAA-mediated short-intracortical inhibition (SICI) as measured using transcranial magnetic stimulation (TMS). However, these studies used fixed TMS parameters, which may not optimally probe GABAA receptor activity for each individual. In the present study, we measured the relationship between stopping efficiency and SICI using a range of TMS parameters. Participants completed a right-hand unimanual stop signal task to obtain a measure of stopping efficiency. Resting-state SICI was measured from the left primary motor cortex using six combinations of interstimulus intervals and conditioning pulse intensities. We also established the parameters which generated the strongest SICI (SICImax) and weakest SICI (SICImin) for each individual. We found that stopping efficiency was significantly predicted by SICI using various TMS parameters, including SICImax. Interestingly, SICImin accounted for a similar proportion of variance in stopping efficiency as SICI measured using other TMS parameters. The findings suggest that the relationship between stopping efficiency and SICI is robust, reliable, and not influenced by the extent to which SICI is optimally probed. 相似文献
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《Journal of stroke and cerebrovascular diseases》2022,31(6):106481
ObjectivesIt is sometimes difficult to differentiate middle cerebral artery disease from moyamoya disease because the two can present similarly yet have different treatment strategies. We investigated whether the presence of a narrow carotid canal and the RNF213 mutation can help differentiate between the two phenotypes.Population and MethodsWe analyzed 78 patients with moyamoya disease, 27 patients with middle cerebral artery disease, and 79 controls from 2 facilities. The carotid canal diameter was measured using computed tomography. The p.R4810K mutation was genotyped by TaqMan assay. A receiver operating characteristics analysis was performed to assess the significance of the carotid canal diameter for the accurate diagnosis of moyamoya disease.ResultsThe carotid canal diameter was significantly narrower in patients with moyamoya disease than in controls. The optimal cutoff values were 5.0 mm for adult males and 4.5 mm for adult females and children (sensitivity: 0.82; specificity: 0.92). Among the patients with middle cerebral artery disease, 18.5% and 25.0% of the affected hemispheres had the p.R4810K mutation and narrow canal (i.e., below the cutoff), respectively, whereas only 3.1% of those had both. Contrastingly, 68.8% of the affected hemispheres in patients with moyamoya disease had both these characteristics. Among the patients with moyamoya disease, those with the p.R4810K mutation tended to have narrower carotid canals.ConclusionsAlthough the presence of a narrow carotid canal or the p.R4810K mutation alone could not be used to distinguish those with moyamoya disease from those with middle cerebral artery disease, the combination of these factors could better characterize the two phenotypes. 相似文献
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BackgroundPain is common in Parkinson's disease, and there is no effective treatment. We conducted a clinical trial to determine whether high-frequency repetitive transcranial magnetic stimulation over the primary motor cortex alleviates musculoskeletal pain in patients with Parkinson's disease.MethodsIn this single-center and double-blind trial, 52 patients with Parkinson's disease and musculoskeletal pain were randomly allocated to 26-member groups receiving 5 sessions of either 20-Hz repetitive transcranial magnetic stimulation or sham stimulation over the primary motor cortex. The participants underwent assessments in the “ON” medication state at baseline, after the fifth session, and at 2- and 4-week follow-up timepoints. The primary outcomes were pain scores on a numeric rating scale. The secondary outcomes were scores on clinical scales assessing motor symptoms, depression, anxiety, autonomic symptoms, sleep quality, and the overall severity of Parkinson's disease.ResultsAnalyses revealed significant group × time interactions for numeric rating scale pain scores (p < 0.001), motor symptom scores (p < 0.001), depression scores (p = 0.009), anxiety scores (p = 0.013), and overall disease severity scores (p < 0.001). Post hoc analyses confirmed that the repetitive transcranial magnetic stimulation group, but not the sham stimulation group, exhibited significant improvements in numeric rating scale pain scores, motor symptom scores, depression scores, anxiety scores, and overall disease severity scores.ConclusionHigh-frequency repetitive transcranial magnetic stimulation over the primary motor cortex may be an effective adjunct therapy for alleviating musculoskeletal pain in patients with Parkinson's disease. 相似文献
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《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy. 相似文献
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Colin Holbrook Marco Iacoboni Chelsea Gordon Shannon Proksch Ramesh Balasubramaniam 《Social cognitive and affective neuroscience》2020,15(12):1350
Research indicates that the posterior medial frontal cortex (pMFC) functions as a ‘neural alarm’ complex broadly involved in registering threats and helping to muster relevant responses. Holbrook and colleagues investigated whether pMFC similarly mediates ideological threat responses, finding that downregulating pMFC via transcranial magnetic stimulation (TMS) caused (i) less avowed religious belief despite being reminded of death and (ii) less group bias despite encountering a sharp critique of the national in-group. While suggestive, these findings were limited by the absence of a non-threat comparison condition and reliance on sham rather than control TMS. Here, in a pre-registered replication and extension, we downregulated pMFC or a control region (MT/V5) and then primed participants with either a reminder of death or a threat-neutral topic. As mentioned previously, participants reminded of death reported less religious belief when pMFC was downregulated. No such effect of pMFC downregulation was observed in the neutral condition, consistent with construing pMFC as monitoring for salient threats (e.g. death) and helping to recruit ideological responses (e.g. enhanced religious belief). However, no effect of downregulating pMFC on group bias was observed, possibly due to reliance on a collegiate in-group framing rather than a national framing as in the prior study. 相似文献
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The pathophysiology of migraine is complex.Neuroimaging studies reveal functional and structural changes in the brains of migraine patients.We sought to explore regional volume differences in intracranial structures in patients with episodic and chronic migraine.Sixteen episodic migraine patients,16 chronic migraine patients,and 24 normal controls were recruited and underwent 3.0 T MRI scanning.The volumes of 142 brain regions were calculated by an automatic volumetric algorithm and compared with clinical variables.Results demonstrated that the volumes of specific regions in the frontal and occipital lobes,and the right putamen,were increased and the volume of the fourth ventricle was decreased in the episodic migraine patients compared with controls.The volumes of the left basal forebrain,optic chiasm,and,the fourth ventricle were decreased in the chronic migraine patients,while the occipital cortex and the right putamen were larger.Compared to episodic migraine patiants,chronic migraine patients displayed larger left thalamus and smaller frontal regions.Correlation analysis showed that headache frequency was negatively correlated with the volume of the right frontal pole,right lateral orbital gyrus,and medial frontal lobes and positively correlated with the volume of the left thalamus.The sleep disturbance score was negatively correlated with the volume of the left basal forebrain.This suggests that migraine patients have structural changes in regions associated with pain processing and modulation,affective and cognitive processing,and visual perception.The remodeling of selective intracranial structures may be involved in migraine attacks.This study was approved by the Ethics Committee of Chinese PLA General Hospital(approval No.S2018-027-02)on May 31,2018. 相似文献